期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2017
卷号：114
期号：42
页码：11223-11228
DOI：10.1073/pnas.1700627114
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The type VII secretion system (T7SS) of Staphylococcus aureus is a multiprotein complex dedicated to the export of several virulence factors during host infection. This virulence pathway plays a key role in promoting bacterial survival and the long-term persistence of staphylococcal abscess communities. The expression of the T7SS is activated by bacterial interaction with host tissues including blood serum, nasal secretions, and pulmonary surfactant. In this work we identify the major stimulatory factors as host-specific cis -unsaturated fatty acids. Increased T7SS expression requires host fatty acid incorporation into bacterial biosynthetic pathways by the S . aureus fatty acid kinase (FAK) complex, and FakA is required for virulence. The incorporated cis -unsaturated fatty acids decrease S . aureus membrane fluidity, and these altered membrane dynamics are partially responsible for T7SS activation. These data define a molecular mechanism by which S . aureus cells sense the host environment and implement appropriate virulence pathways.
